Trimming device for trimming the edges of workpiece cuts

ABSTRACT

AN EDGE TRIMMING DEVICE FOR TRIMMING THE EDGES OF WORKPIECE CUTS CONSISTING OF TEXTILES, THIN LEATHER OR SIMILAR MATERIAL, AT WHICH THE WORKPIECE CUTS ARE RECEIVED IN WORKPIECE HOLDERS SECURED TO A ROTARY-TABLE. THE TRIMMING TOOLS ARE ARRANGED IN A HOUSING LIKE A SEWING MACHINE, AND THE SHAPE OF THE CUTS IS DETERMINED BY TEMPLATES WHICH ARE PLACED BELOW THE WORKPIECE HOLDERS AND COOPERATE WITH A DRIVEN MAGNETIC ROLLER. A DEVICE FOR DISCHARGING THE CUTTING SCRAP OUT OF THE DEVICE IS PROVIDED.

NOV. 16, 1971 JUNEMANN 3,620,312

7 TRIMMING DEVICE FOR TRIMMING THE EDGES OF WORKPIECE CUTS Filed Jan. 29, 1970 2 Sheets-Sheet l H. JUNEMANN Nov. 16, 1971 TRIMMING DEVICE FOR TRIMMING THE EDGES OF WORKPIECE CUTS Filed Jan. 29, 1970 2 Sheets-Sheet 2 7 04 8 3 7 m U 5 2 6 3 IQ II II b 5 K$-$MM 5. $27! 5 IL In l w 7 3 h 3 Z l m 2 H A V A 1 3 8 1 1 3 2 m 2 a 7 N 5 2 2 1 4 h 0 7 s United States Patent 3,620,112 TRHVIMING DEVICE FOR TRIMMING THE EDGES F WORKPIECE CUTS Hubert Jiinemann, Bielefeld, Germany, assignor to Kochs Adlernahmaschinen Werke AG, Bielefeld, Germany Filed Jan. 29, 1970, Ser. No. 6,697 Claims priority, application Germany, Jan. 30, 1969, P 19 04 385.7 Int. Cl. B26d 7/06 US. Cl. 83-98 Claims ABSTRACT OF THE DISCLOSURE An edge trimming device for trimming the edges of workpiece cuts consisting of textiles, thin leather or similar material, at which the workpiece cuts are received in workpiece holders secured to a rotary-table. The trimming tools are arranged in a housing like a sewing machine, and the shape of the cuts is determined by templates which are placed below the workpiece holders and cooperate with a driven magnetic roller. A device for discharging the cutting scrap out of the device is provided.

BACKGROUND OF THE INVENTION This invention relates to a device for trimming of coarsely cut edges of workpiece cuts of textiles, thin leather or similar materials which are received in workpiece holders arranged in a rotary table and automatically fed to the trimming device.

There is already known a machine provided with a housing similar to a sewing machine, a punch instead of a needle and a die instead of a throat plate. This cutting machine is used for cutting or punching fabrics, leather, cards or paper and is described in the British Pat. 6,068 AD. 1901.

Furthermore, an automatic sewing device is disclosed in German utility Pat. No. 1,942,394.

It is provided with a device for trimming coarsely cut workpieces consisting of textiles, thin leather, plastics or similar materials. This device comprises a punch in the form of a steel pin and a die, which arereceived in a housing similar to a sewing machine, and in which the reciprocating needle bar carries the punch and the throat plate receives the die. In this automatic sewing device there is provided a swingable hinged arm, opposite to the sewing machine, for receiving the trimming device and a magnetic roller moving along a template. The axis of the magnetic roller is in the imaginary elongated axis of the punch.

Experience has shown, that the trimming tools used in this last mentioned device have a short life span. This insufficiency is due to the fact that, in order to prevent a wavelike formed cutting edge, the punch has to operate at a high cutting speed in proportion to the feed of the workpiece, in order to prevent the formation of a wavelike cutting edge. Since, in consequence of the fine feed per cut, only a part of the cutting surface is loaded, the punch is deflected from the cutting edge. It has been further shown that cutting tools subjected only to slight wear and tear cannot assure an unobjectionable cutting of thin workpieces, such as thin nylon fabrics, since the fine fibers are drawn in between the punch and the die. It is an object of the invention to provide a device for automatically trimming the edges of coarsely cut workpieces to a finished size, which is necessary for the subsequent treatment, and which will correspond to the dimensions and forms of templates.

It is a further object of the invention to provide an improved trimming device, which will permit an unobjec- 'ice tionable cutting of the edges of workpieces having a small radius of curvature.

A further object of the invention is to create a trimming device which can be used in connection with a rotary table holding the workpieces to be trimmed.

Another object of the invention is the provision of means for discharging the cutting scrap from the device.

SUMMARY According to the invention the above objects are achieved by means of a device which includes a driven rotary table, a plurality of workpiece holders and templates with inner raceways, secured to said rotary table, a similar housing to that of a sewing machine, having a veritcally reciprocating bar, for carrying the housing and moving it in a horizontal plane, a driven magnetic roller for engaging with the inner raceway of the templates, a trimming means which comprises a vertically reciprocating blade having a cutting edge and which is carried by the reciprocating bar, and a counterknife cooperating with the cutting edge of the reciprocating blade, while the operative part of the cutting blade edge is in 'the imaginary elongated axis of the magnetic roller, and the reciprocating blade and the counterknife are rotatably arranged about said axis.

The reciprocating blade and the counterknife are received in a guide sleeve which is pivoted in the arm of the housing. For this purpose, there are provided a substantially cylindrical blade holder carrying the blade, which is axially slidable and rotatably received in the guide sleeve, a knife holder carrying the counterknife, which is pivoted in the guide sleeve, and a spring for pressing the counterknife against said vertically reciprocating blade.

The blade holder is rotatably received in the reciprocating bar by means of an engaging piece, and a clamping means is provided for connecting the engaging piece to the bar.

The workpiece holders are provided with a lower clamping plate having chamfered edges at the outer contours, and the knife holder is formed with a beveled cant. Spring means acting upon the guide sleeve are provided for pressing the beveled cant of the knife holder to the chamfered edges of the clamping plate.

The cylindrical blade holder is further provided with an axial bore and an opening below the blade communicating with the bore. An air nozzle, movable with the guide sleeve, is provided, the outlet of which is directed towards the opening for blowing the cutting scrap through the axial bore downwards.

BRIEF DESCRIPTION OF "II-IE DRAWINGS FIG. 1 is a front elevational view of a rotary table provided with workpiece holders and a trimming device;

FIG. 2. is a top plan view of the rotary table and the trimming device drawn to a reduced scale;

FIG. 3 is a partial top plan view and a part of the templates, substantially corresponding to FIG. 2;

FIG. 4 is a section on line 'IVIV of FIG. 2;

FIG. 5 is a section on line VV of FIG. 4;

FIG. 6 is a partial top plan view of the device;

FIG. 7 is a section on line VIIVII of FIG. 5;

FIG. 8 is a section on line VIIIVIII of FIG. 4;

FIG. 9 is a perspective elevation of the trimming tools.

DESCRIPTION OF THE PREFERRED EMBODIMENT The device is carried by a support 1 (FIGS. 1 to 3) 0 in which a vertical shaft 2 is pivoted and driven by a workpiece holders 6 consisting of a lower clamping plate 8 carrying workpieces 7, and an upper clamping plate 9. Below the workpiece holders 6 there are provided templates 10 secured to the rotary table 5. Pivoted on the support 1 is an intermediate link arm 11 (FIGS. 2, 3) to the free end of which a movable link arm 12 is pinjointed. In the latter is received a roller 13 (FIG. 1) which is magnetizable by means of a coil 14 and driven by a motor 15 through a gearing 16.

The movable lin'k arm 12 carries a housing 17 having a work-supporting arm 18, a standard 19 and an overhanging arm 20 which terminates in a head 21. In the overhanging arm 20 of the housing 17 there is pivoted an arm shaft 21', which is driven by a motor 22 by means of a belt 23. A vertically reciprocating bar 24 is supported in the head 21, the axis of which is in the imaginary elongated axis of the magnetic roller 13. The bar 24 is driven by the arm shaft 21'.

As may be seen in FIGS. 4 to 9, a trimming mechanism is inserted in the work-supporting arm 18. The trimming mechanism comprises substantially a blade 25 and a counterknife 26. The blade 25 is secured by means of a screw .28 to a substantially cylindrical blade holder 27, which is movable up and down and pivoted in a guide sleeve 29. The guide sleeve 29 is pivoted in a bushing 30 which is connected with a plate 31 secured to the work-supporting arm 18 by means of screws 32.

At its upper end, the blade holder 27 is formed with slots 33, 34 (FIG. 3), which serve for receiving an engaging piece 35 having a cylindrical shank and which is inserted in a clamping screwing 36 provided in the reciprocating bar 24. Furthermore, the blade holder 27 has a cutout 37 for locating the blade 25 and an axial bore 38, which forms an opening 39 below the blade 25 (FIGS. 8 and 9). The upper edge 40 of the tubular part of the blade holder 27 is formed with a downwardly sloping edge.

The operative part 41 of the cutting edge of the blade 25 is in the imaginary elongated axis of the magnetic roller 13 and the reciprocating bar 24 and cooperates with the counterknife 26, which is secured to a knife holder 42, formed for this purpose with an U-shaped recess'43 (FIGS. 6 and 9). The knife holder 42 carries a guide piece 44 having a beveled cant, with which can abut the lower clamping plates 8 provided with chamfered edges 46. Secured in the knife holder 42 is a shaft 47, which is pivoted in a bore 48 in the guide sleeve 29. On the free end of the shaft 47 is arranged a clamping lever 49, in which is inserted a bolt 50 (FIGS. 7 and 9) under the tension of a spring 51 and abuting against a pin 52, which is disposed in the guide sleeve 29. Thus, the counterknife 26 is pressed elastically against the blade 25.

Arranged on the guide sleeve 29 is a clamping ring 53 (FIGS. 4 and 5) provided with a groove 54 for receiving a string 55, one end of which is secured to the clamping ring 53 and the other end of which is connected with a tension spring 56 (FIGS. 1 and 6). The free end of the tension spring 56 is secured to a wall of the worksupporting arm 18. The string 55 is guided in the groove 54 in such a manner, that the stretched tension spring 56 has a tendency to effect a revolution of the guide sleeve 20 in a clockwise direction, in order to press the guide piece 44 of the knife holder 42 against the lower clamping plate 8 of the workpiece holder 6.

A holding member 57 (FIGS. 4, 5) is secured to the knife holder 42, which carries an air nozzle 58, connected to a compressed air source (not shown) by means of a hose line 59. The jet stream leaving the nozzle outlet 60 causes the cutting scrap to be blown away downwards from the trimming device, through the opening 39 and the bore 38.

The operation of the trimming device is as follows:

After inserting the workpieces to be trimmed into the workpiece holders 6 and switching on the motor 3, the

rotary table 5 will be turned in the direction of the arrow (see FIG. 2). By switching on the coil 14 and the motor 15, the roller will be pressed against the template 10 and will move alongside of it. After switching on the motor 22, the blade holder 27 will be moved up and down in a relatively fast sequence, with only the part 41 (FIG. 5) of the blade 25 cooperating with the counterknife 26. Thus, relatively short single cuts will be produced which will substantially cross the axis of the guide sleeve 29 and the roller 13. The tension spring 56 will cause the guide piece 44 of the knife holder 42 to abut against the lower clamping plate 8 during the trimming of the straight as well as the curved cutting edges.

What I claim is:

51. An edge trimming device for trimming the edges of workpiece cuts consisting of textiles, thin leather or similar material, comprising a support member, a first driven shaft for vertical rotation on said support member, a rotary table carried by said first driven shaft, a plurality of workpiece holders and arm supports having templates with inner raceways, secured to said rotary table, a housing similar to a sewing machine having a work-supportlng arm, a standard, an overhanging arm, a head, a vertically reciprocating bar arranged in said head, an arm shaft mounted in said overhanging arm, for driving said reciprocating bar, and a motor for driving said arm shaft, a movable link arm carrying said housing, an intermediate link arm supporting said movable link arm and pivoted to said support member, a second driven shaft mounted in said link arm, a magnetic roller secured to said second. driven shaft for engaging with the inner raceways of said templates, said second driven shaft being aligned axially with said reciprocating bar, trimming means including a vertically reciprocating blade having a cutting edge and carried by said reciprocating bar, and a counterknife cooperating with said cutting edge of said reciprocatlng blade, the operative part of said cutting edge being 1n the imaginary elongated axis of said magnetic roller, said reciprocating blade and said counterknife being rotatably arranged about said axis.

2. An edge trimming device according to claim 1, wherein said work-supporting arm of said housing is provided with a guide sleeve for receiving said reciprocating blade and said counterknife, said guide sleeve being r0- tatable in said work-supporting arm.

6. An edge trimming device as claimed in claim 1, further comprising a guide sleeve pivoted in said worksupporting arm of said housing for receiving said counterknife, and a substantially cylindrical blade holder carrying said blade, said blade holder being axially slidable and rotatably received in said guide sleeve.

4. An edge trimming device as claimed in claim 1, further comprising a guide sleeve pivoted in said worksupporting arm of said housing, a substantially cylindrical blade holder carrying said blade and being axially slidable and rotatably received in said guide sleeve, a knife holder carrying said counterknife and pivoted in said guide sleeve, and a spring for pressing said countenknife against said vertically reciprocating blade.

'5. An edge trimming device as claimed in claim 1, further comprising a guide sleeve pivoted in said supporting arm of said housing, a substantially cylindrical blade holder carrying said blade and being rotatably received in said guide sleeve, a knife holder carrying said counterknife and pivoted in said guide sleeve, a spring for pressing said counterknife against said vertically reciprocating blade, said workpiece holders being provided with a lower clamping plate having chamfered edges at the outer contours, said knife holder being formed with a beveled cant and a spring means acting upon said guide sleeve, for pressing said beveled cant of said knife holder to said chamfered edges of said clamping plates.

6. An edge trimming device as claimed in claim 1, further comprising a guide sleeve pivoted in said worksupporting arm of said housing for receiving said counterknife, a substantially cylindrical blade holder carrying said blade, said blade holder being axially slidable and rotatably received in said guide sleeve, an engaging piece for rotatably receiving said cylindrical blade holder, and a clamping means attached to said reciprocating bar, for connecting said engaging piece to said bar.

7. An edge trimming device as claimed in claim 3, wherein said cylindrical blade holder is provided with an axial bore and an opening below said blade, said bore communicating with said opening for discharging cutting scrap through said bore downwards.

8. An edge trimming device as claimed in claim 1, further comprising a guide sleeve pivoted in said worksupporting arm of said housing for receiving said counterknife, a substantially cylindrical blade holder carrying said blade, said cylindrical blade holder being provided with an axial bore and an opening below said blade, said bore communicating with said opening, and an air nozzle having a nozzle outlet and being movable with said guide sleeve, said nozzle outlet being directed towards said opening for blowing cutting scrap through said axial bore downwards.

6 9. In an edge trimming device as claimed in claim 5, wherein said guide sleeve is provided with a groove, a string disposed in said groove and secured to said guide sleeve, and a tension spring arranged between said string and the work-supporting arm.

10. An edge trimming device as claimed in claim 8, wherein said cylindrical blade holder is provided with a downwardly sloping edge portion at said opening.

References Cited UNITED STATES PATENTS 3,376,836 4/1968 Nicolay 83902 X FOREIGN PATENTS 630,015 10/ 1949 Great Britain 83220 FRANK T. YOST, Primary Examiner US. Cl. X.R.

834ll, 565, 583, 632, 636, 685, 689, 697 902 925 CC 

